Issue #8496: make mailcap.lookup() always return a list, rather than an iterator.

Patch by Gregory Nofi.

Lib/mailcap.py

@@ -164,7 +164,7 @@ def lookup(caps, MIMEtype, key=None):
     if MIMEtype in caps:
         entries = entries + caps[MIMEtype]
     if key is not None:
-        entries = filter(lambda e, key=key: key in e, entries)
+        entries = [e for e in entries if key in e]
     return entries
 
 def subst(field, MIMEtype, filename, plist=[]):

Misc/NEWS

@@ -326,6 +326,9 @@ C-API
 Library
 -------
 
+- Issue #8496: make mailcap.lookup() always return a list, rather than an
+  iterator.  Patch by Gregory Nofi.
+
 - Issue #8195: Fix a crash in sqlite Connection.create_collation() if the
   collation name contains a surrogate character.